For some benchmarks, this 4000 euro, super-computing desktop PC surpassed a 256-node, dual proc. supercomputer that the University of Antwerp paid over 3 Million euro's for some three or four years ago. (I wonder if they're embarrassed about that?! )

"... NVIDIA CUDA programming model which makes all eight GPUs work in parallel"

That looks like a very nice gamin' rig . Even one of those (dual GPU) cards can probably play the latest games @ insane qualities. Though, apparently the GPU's don't communicate with each other, just with the CPU.

I think the CPU in their set up is basically a smart data switch. There is a way to sync up the GPUs, (SLI ??) but I've never had more than one of these cards in my hands!

This GPU is amazing - it can do over 12,000 threads at once --- and that's just one card. Realistic however - according to the docs I've looked at - is about 5,000 threads. The system mentioned above has 4 cards = 20,000 to 48,000 threads all at the same time. (And they can avoid thread lock!)

Though, apparently the GPU's don't communicate with each other, just with the CPU.

No, not in the configuration they used at the univeristy (see starting post), but the GPU's can be linked together using Nvidia's "SLI" technology --- I can only imagine what 10 of these cards linked together could do - besides heat your house in Winter Near real-time holograms anyone?